module.exports={
        origin: function(ctx) {
         
          //return 'http://localhost:3000';
          return '*'
        },
        exposeHeaders: ['WWW-Authenticate', 'Server-Authorization'],
        maxAge: 5,
        credentials: true,
        allowMethods: ['GET', 'POST', 'DELETE', 'patch'],
        allowHeaders: ['Content-Type', 'Authorization', 'Accept'],
        exposeHeaders: ['WWW-Authenticate', 'Server-Authorization'] //设置获取其他自定义字段
}